How Sparkling Wine is Made
Not all that sparkles is necessarily great wine, but great sparkling wine offers a uniquely exciting experience.
There are four main methods of putting a sparkle (always carbon dioxide) into wine:
This, the so-called ‘bicycle pump method’, is no more sophisticated than simply pumping carbon dioxide into a tankful of wine. It is also used for fizzy soft drinks and achieves a bubble just as crude and short-lived in wine. If a bottle opens with a tremendous gush and then subsides rapidly into a wine that is almost flat, then the carbonation method was probably used.
Most wines should be good enough to warrant this particular sparkling treatment at the very least. A vat or cuve of wine has a mixture of sugar and yeast added to it. The yeast provokes a second fermentation which produces alcohol but which, as in all fermentations, gives off carbon dioxide as a side-effect. (Cellar workers are warned to beware putting their head inside a vat of fermenting must of any sort. So much carbon dioxide is given off it could make them faint.) The vats used for making awe close wines are sealed and the gas therefore forced to dissolve in the wine. Provided the wine is bottled under pressure, the bubbles will stay in the bottle until it is opened. This is the most common way of making wine fizzy and is used for most French sparklers labelled vin mousseux. This is also known as the tank or Charmat method.
The more contact there is between the lees of the second fermentation and the wine, the more character the sparkling wine will have. The transfer method uses this by bottling the mixture of wine, yeast and sugar, and allowing the second fermentation to take place in bottle. The wine is rested for a time afterwards before the sediment is filtered out under pressure and the wine put into another bottle. This technique is popular in Germany, where Sekt is made.
The ‘champagne method’ is the most involved of all, but should result in the finest, longest-lasting fizz. The mixture of wine, yeast and sugar is put into the bottle in which it is eventually sold which is stored horizontally. The second fermentation takes place, leaving the sediment on the underside where it can stay for years, adding richness and complexity to the wine. The bottle is gradually shaken and moved so that it is vertical and upside down, with the sediment resting in the neck. When the neck is frozen and the bottle opened, the sediment pops out in a neat plug. Once the bottle has been topped up with a mixture of wine and sugar, a new cork is inserted. A wine labelled Brut has very little sugar added, while one labelled Sec or Dry has a bit more and a Rich is positively sweet.
These methods rely heavily on the quality of the still wine used as a base. It is generally accepted that the finest base wines come from the Chardonnay and Pinot vines of the Champagne region in north-east France, and it is only these wines, made bubbly by the methode champenoise, that may be called champagne. Everything else has to be called, rather primly, ‘sparkling wine’. Most champagne is very dry and labelled simply with the name of the ‘house’ that made it. About one bottle in five is wine from a single year, but blending is the key to champagne-making and the great majority of the wine is NV, meaning non-vintage: a blend of wines from different years.
Any French sparkling wine that is allowed to put Appellation Controlee on the label will have been made by the methode cbampenoise. Some of the finest and lightest come from Chenin Blanc grapes grown in Saumur and Vouvray, both in the Loire, though there are some good Cremants (which has come to be synonymous with sparkling wine but should be slightly less fizzy) from Alsace and Bourgogne in Burgundy. Blanquette de Limoux, Clairette de Die and Saint Peray are all very creditable AC sparklers from southern France, though the biggest sellers tend to be non-AC branded wines – usually made by the cuve close method.
Spain produces enormous quantities of methode champenoise wine in Catalonia. It has a fuller flavour than champagne but can be very well-made and good value. Enormous progress has also been made in northern Italy, now making some very fine methode champenoise dry white wine. Almost all wine regions turn out some sparkling wine, of varying quality. The Russians drink huge quantities of it, and California has seen enormous investment over the last few years- most of it from Europe, and much of it from Champagne!